Steve Garnett, DVM, DACVS-SA Dogs and Cats Veterinary Referral and Emergency April 30, 2017
Overview Anatomy review Cystotomy Urethrotomy Urethrostomy What s New!
Anatomy
Anatomy
Cystotomy Indications Cystic/urethral calculi Urethral obstruction Calcium oxalate calculi Incidental or non-obstructive calculi????? Neoplasia Ureteral procedure
Cystotomy Preoperative Management Radiographs/ultrasound Urinalysis Antibiotics Perioperative IV antibiotics do not appear to impact culture results from bladder/calculi Buote NJ, et al. The effect of preoperative antimicrobial administration of culture results in dogs undergoing cystotomy. JAVMA. 1012;241:1181-1189.
Cystotomy Technique Ventral midline (paramedian in males) Pack off Stay sutures Bladder spoon Retro- and antegrade catheterization and flushing Single or double layer continuous closure Appositional vs. inverting Interrupted vs. continuous Leak test
Cystotomy
Cystotomy
Cystotomy Postoperative Care Postoperative radiograph Stone analysis Analgesia Mild hematuria and stranguria expected +/- antibiotics
Cystotomy Complications Remaining calculi (4-20%) Uroabdomen (1-3%) Urethra or ureteral trauma (2-3%) Surgical site infection (3%)
Cystotomy Tips Retrograde flushing of urethral calculi Limited incision, exteriorize bladder Males ventral midline through body wall Ventral cystotomy Flush, flush, and flush again
Laparoscopic Assisted Cystotomy Minimally invasive alternative to open cystotomy One or two portals, each approximately 1-2cm Males and females Dogs and cats Not practical in very small dogs/cats
Pinel CB et al. Laparoscopic-assisted cystotomy for urolith removal in dogs and cats 23 cases. Can Vet J. 2013;54:36-41.
Laparoscopic Assisted Cystotomy Advantages Less painful Smaller incisions Thorough evaluation of bladder Shorter hospital stays Disadvantages More expensive More time consuming initially Pinel CB et al. Laparoscopic-assisted cystotomy for urolith removal in dogs and cats 23 cases. Can Vet J. 2013;54:36-41. Arulpragasam SP, et al. Evaluation of costs and time required for laparoscopicassisted versus open cystotomy for urinary cystolith removal in dogs: 43 cases (2009-2012). JAVMA. 2013;243:703-708. Singh, A et al. Perioperative characteristics of dogs undergoing lopen versus laparoscopic- assisted cystotomy for treatment of cystic calculi: 89 cases (2011-2015). JAVMA. 2016;249:1401-1407.
Calculi Prevention Calcium oxalate Correct hypercalcemia if present Aciduria prevention (ph 6.5-8.0) Diet (Hill s u/d, Royal Canine Urinary SO) +/- potassium citrate if ph <6.5 after diet change Increase water intake (USG <1.020) Miniature Schnauzers Higher recurrence rate Consider Hill s w/d, c/d or g/d if hypertriglyceridemic UA every 3-6 months, image every 6-12 months https://www.vetmed.umn.edu/centers-programs/minnesota-urolithcenter/recommendations Allen HS, et al. Associations of diet and breed with recurrence of calcium oxalate cystic calculi in dogs. JAVMA. 1015;246:1098-1103
Calculi Prevention Struvite Treat, prevent and monitor for infections! Culture and sensitivities Weight loss, episioplasty Increase water intake UA and urine culture/sensitivity q3-6 months Diet Urine acidifier (ph <6.5) May increase risk of CaOx calculi Low in phosphorus and magnesium https://www.vetmed.umn.edu/centers-programs/minnesota-urolithcenter/recommendations
Urethrotomy Indications Urethral calculi unable to be hydropulsed Temporary bypass due to other Location Pre-scrotal ideal due to superficial location Usually over calculi
Urethrotomy Procedure 2cm skin and subcutaneous incision Identify urethra Longitudinal incision on midline Remove calculi and advance catheter Closure vs. second intention 4-0 or 5-0 monofilament absorbable suture, simple continuous or simple interrupted in urethra. Routine SQ and skin closure
Urethrotomy Risks Post-op bleeding not life threatening Stricture uncommon Post-op care E collar, cage rest, antibiotics, analgesics Kept in an easy to clean area Petroleum jelly around stoma until healed Calculi prevention!
Urethrotomy Tips Owner preparation pre op before every cystotomy Gentle tissue handling Small gauge suture for closure Owner preparation post op - bleeding
Urethrostomy - Dog Indications Permanent injury/obstruction of distal urethra Neoplasia Decrease likelihood of obstruction from recurrent urinary calculi Because of risks try to avoid if possible
Urethrostomy - Dog Procedure Pre-scrotal, scrotal, perineal and prepubic Elliptical incision at base of scrotum/remnant Dissect to urethra and incise over catheter (3-4cm in length) Tacking sutures to pull urethra ventrally SC or SI small gauge non absorbable mucosa to skin Bilbrey SA, et al. Scrotal urethrostomy: a retrospective review of 38 dogs (1973 1988). J Am Anim Hosp Assoc 27:560, 1991. Newton JD, et al. Simple continuous closure of canine scrotal urethrostomy: results in 20 cases. J Am Anim Hosp Assoc 32:531, 1996
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Urethrostomy - Dog Risks Bleeding not life threatening Continuous closure may reduce the duration Hematuria Stricture of stoma Urine scald Urinary tract infection Recurrent calculi and obstruction
Urethrostomy - Dog Post op care E collar, antibiotics, activity restriction, analgesics Monitor for urine scald Prepare owners for bleeding Monitor for urinary tract infections Calculi prevention
Urethrostomy - Dog Tips Use a catheter Careful tissue handling Careful apposition of mucosa to skin Minimize tension Large stoma it will shrink by a third to half
Perineal Urethrostomy in Cats Indications Recurrent urinary obstruction Non-catheterizable urinary obstruction Urethral strictures or tears
Perineal Urethrostomy in Cats Preoperative management Treat azotemia, dehydration and electrolytes derangements Rule out other etiologies (calculi, infection) Owner education
Perineal Urethrostomy in Cats Analgesia Systemic Regional epidural Purse string in anus Positioning Dorsal vs. sternal
Perineal Urethrostomy in Cats Technique Elliptical incision around penis and prepuce Ventral dissection, freeing ischiocarvernosis muscles from the pelvis Limited dorsal dissection to the level of the bulbourethral glands Transect retractor penis muscle Catheterize urethra and make urethral incision Suture urethral mucosa to skin
PU in Cats
Perineal Urethrostomy in Cats Postoperative Care Prevent local trauma E-collar Do not clean area Shredded paper/yesterday s News Litter Analgesics (Fentanyl Patch or Buprenex, +/- NSAID) Antibiotics Activity Restriction
Perineal Urethrostomy in Cats Complications (50%) Stricture and re-obstruction Subcutaneous urine leakage Dehiscence Cystitis (10-25%) 86% long term success rate Ruda L, et al. JSAP. 2012;53:693-698.
Perineal Urethrostomy in Cats Tips Ventral dissection Large stoma size Suture choice Suture technique Prevent self trauma
What New! Urethral stenting Ureteral obstructive treatment Ureteral stenting Subcutaneous ureteral bypass
Urethral Stenting Indications Urethral obstruction Neoplasia TCC Prostatic carcinoma Strictures Reflex dyssynergia Extraluminal compression
Blackburn A, et al. JAVMA 2013
Urethral Stenting Outcome Malignant causes Palliative procedure Survival times (MST 78 days) Improved clinical signs resolved obstruction (85-97% success rate) Incontinence common 26-39% Stranguria common 45% Risk of migration, infection, re-obstruction Usually combined with an NSAID/Chemo Blackburn A, et al. JAVMA 2013 McMillan S, et al. JAVMA 2012
Urethral Stenting Outcome benign causes Resolves obstruction Incontinence 37.5% Good long term prognosis Blackburn A, et al. JAVMA 2013 McMillan S, et al. JAVMA 2012
Ureteral Obstruction Causes Calculi 98% calcium oxalate Strictures Neoplasia Clinical Signs Vomiting, lethargy, inappetence Abdominal pain Azotemia, hyperkalemia
Ureteral Obstruction Traditional treatments Length of obstruction directly correlated with permanent loss of GFR Medical therapy 33% mortality rate Better with small, distal 1/3 rd calculi Surgery 18-39% mortality rate Minimally Invasive Techniques Stents 7.5% mortality rate, MST 500 days Subcutaneous ureteral bypass Berent AC, et al. JAVMA 2014
Ureteral Stents
SUBs
Questions
Resources Tobias KM and Johnston SA. Veterinary Surgery: Small Animal. Elsevier Saunders, St. Louis. 2012. Fossum TW. Small Animal Surgery; Fourth Edition. Elsevier Mosby, St. Louis. 2013. Tobias KM. Manual of Small Animal Soft Tissue Surgery. Blackwell, Ames, 2010.